New research from the Centers for Disease Control and
Prevention (CDC) reveals an additional two million kids have attention attention-deficit/hyperactivity
disorder compared to stats collected nearly a decade earlier.

One million more kids are also taking medications to treat
their ADHD, according to the new data collected from 2011-2012.

"The number of
U.S. households impacted by childhood diagnoses of ADHD is growing," Susanna
Visser, an epidemiologist with the CDC's National Center on Birth Defects and
Developmental Disabilities, said in a press release. "When children diagnosed with ADHD receive proper treatment, they have the best chance of thriving
at home, doing well at school, and making and keeping friends."

ADHD is considered a neurobehavioral disorder and it
often lasts into adulthood. It is characterized by problems paying
attention and controlling impulses, daydreaming, being overly active with
squirming or fidgeting, and having difficulty getting along with others.

For the study, researchers compared data sets collected from
the National Survey of Children's Health to calculate the number of U.S.
children and adolescents between the ages of 4 and 17 that received an ADHD
diagnosis from a doctor.

They found for 2011-2012, 6.3 million children received an
ADHD diagnosis, which represented a 42 percent rise over 2003-2004 rates. That
means about 11 percent of U.S. kids and adolescents currently are diagnosed
with ADHD.

Recent studies have also found rises in ADHD diagnosis rates
over the past decade, ranging from 24 percent to 53 percent.

As for medication, more than 3.5 million of America's youth
are taking ADHD drugs, a 28 percent rise over rates collected in 2007-2008.

Federal health officials felt not nearly enough kids with
ADHD were receiving treatment: Almost 18 percent of the kids did not receive
mental health counseling or medication in 2011-2012. Of them, one-third were
reported to have moderate or severe ADHD.

"This finding raises concerns about whether these
children and their families are receiving needed services," said Dr.
Michael Lu, senior administrator for the government's Health Resources and
Service Administration, said in a written statement.

About half of the children were diagnosed by age 6, but
about half of those with severe cases of ADHD received a diagnosis around 4
years old.